Tool assembly unit

ABSTRACT

The present invention provides a tool assembly unit for coupling a tool and a tool holder including a measuring device which determines the position of the tool with respect to the tool holder, an alignment device coupled to the measuring device which receives the tool holder, a moveable rod slideably disposed on the alignment device and coupled to the tool which moves the tool with respect to the tool holder to a desired position as measured by the measuring device. The tool may be affixed to the tool holder by heat shrinking.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Serial No. 60/315,630, filed Aug. 29, 2001.

FIELD OF THE INVENTION

The present invention relates generally to heat shrink tools and moreparticularly to a device for accurate assembly of a tool to a toolholder by the heat shrink method.

BACKGROUND OF THE INVENTION

Connecting a tool to a tool holder by the heat shrink method is awell-known process. An example of the general process is described inU.S. Pat. No. 5,311,654 issued to Harold D. Cook on May 17, 1994. Theheat shrink process is typically used with a tool holder having a borefor receipt of a tool having a shank. The tool holder is heated toexpand the tool holder bore. The shank of the tool is then inserted intothe bore. As the tool holder cools, the bore shrinks around the shankholding the shank within the tool holder.

The heat shrink method is an effective method for connecting a tool to atool holder. However, in most applications, the tool must be preciselymounted within the tool holder or the tool holder cannot be used. Itshould be appreciated that these tools are typically used in operationsthat require very precise alignment and positioning. Slight variationsin the alignment between tool and tool holder results in the productionof defective parts. One of the major disadvantages of known methods forconnecting a tool to a tool holder using the heat shrink method is theneed to measure each tool and tool holder and the inaccuracy that canresult from these repetitive measuring operations. Human error is asignificant factor. A worker must measure the tool length and the toolholder length and then adjust the position of the tool to get theappropriate overall length. To reduce human error somewhat, anothermethod employs a pre-qualified measuring rod to determine theappropriate depth of the tool within the tool holder. When this rodwears, the positioning is wrong and resultant tools and tool holderscannot be used. Furthermore, the heat shrink process must be donequickly to avoid down time when changing tools. If the heat shrinkmethod is slow, tool changes will be slow resulting in the overallslowing of the entire operation in which the tool and tool holder arebeing used.

Accordingly, it would be advantageous to provide a tool assembly unitfor rapidly and precisely connecting a tool to a tool holder.

SUMMARY OF THE INVENTION AND ADVANTAGES

It is an object of the present invention to provide a tool assembly unitfor coupling a tool and a tool holder. The unit includes a measuringdevice adapted to determine the position of the tool with respect to thetool holder, an alignment device coupled to the measuring device andbeing adapted to receive the tool holder, a moveable rod slideablydisposed on the alignment device and coupled to the tool, with the rodbeing adapted to move the tool with respect to the tool holder to adesired position as measured by the measuring device.

It is another object of the present invention to provide a tool assemblyunit for coupling a tool and a tool holder by heat shrinking. The unitincludes a measuring device adapted to determine the position of thetool with respect to the tool holder, an alignment device coupled to themeasuring device and being adapted to receive the tool holder, a heatingdevice slideably mounted on the alignment device and defining a bore forsliding a tool therethrough with the heating device adapted to beremovably mounted on the tool holder for heating the tool holder, amoveable rod slideably disposed on the alignment device and beingadapted to be coupled to the tool, with the rod being further adapted tomove the tool with respect to the tool holder to a desired position asmeasured by the measuring device.

It is still another object of the present invention to provide a methodfor coupling a tool with a tool holder using a tool assembly unitincluding a measuring device coupled to an alignment device and amoveable rod slideably disposed on the alignment device. The methodincludes the steps of mounting the tool holder on the alignment device,coupling the moveable rod to the tool, measuring an actual relativeposition between the tool and tool holder, moving the tool within thetool holder until the actual relative position of the tool relative tothe tool holder is equal to a desired position, and removing the toolholder and the tool from the alignment device.

It is still another object of the present invention to provide a methodfor coupling a tool with a tool holder by heat shrinking using a toolassembly unit including a measuring device coupled to an alignmentdevice having a heating device slideably mounted thereon and a moveablerod slideably disposed on the alignment device. The method includes thesteps of mounting the tool holder on the alignment device, heating thetool holder, coupling the moveable rod to the tool, measuring an actualrelative position between the tool and the tool holder, moving the toolwithin the tool holder until the actual position of the tool relative tothe tool holder is equal to a desired position, shrinking the toolholder around the tool, and removing the tool holder and the tool fromthe alignment device.

The subject invention provides many advantages over conventional toolassembly units by providing a tool assembly unit that rapidly andprecisely couples a tool and a tool holder. One of the major advantagesis reducing or eliminating the need to measure each tool and toolholder, thereby significantly reducing the inaccuracy that can resultfrom these repetitive measuring operations due to human error. Anotheradvantage is that rod wear does not result in improper positioning ofthe tool relative to the tool holder, thereby reducing cost by reducingthe number of resultant tool assembly units that cannot be used.Furthermore, the tool assembly unit of the present invention permits theheat shrink process to be done quickly to avoid down time when changingtools, thus reducing tool change time and encouraging an efficientassembly operation.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a perspective view of a tool assembly unit;

FIG. 2 is a perspective view of an alignment device used in the toolassembly unit of FIG. 1; and

FIG. 3 is an elevational view of the alignment device of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the Figures, wherein like numerals indicate like orcorresponding parts throughout the several views, a tool assembly unitis generally shown at 10. The tool assembly unit 10 includes a measuringdevice shown generally at 12, a heating device shown generally at 14,and an alignment device shown generally at 16. A controller 15 controlsthe various operations of the tool assembly unit 10. The controller 15includes a control panel 18 and a display screen 20. In the disclosedembodiment, a work table 22 is also shown for supporting the toolassembly unit 10.

The measuring device 12 is a standard tool measuring device such as, forexample, a microset unit sold by Tooling Systems Division ofFrankenmuth, Mich. The measuring device 12 includes an optical viewer 24mounted on a vertical tower 26. The optical viewer 24 in the disclosedembodiment is connected to the controller 15. In use, the desired lengthof the assembled tool and tool holder is inputted into the controller 15which automatically adjusts the optical viewer 24 to the correct heightalong the tower 26. In operation, once the tool 36 is correctlypositioned with respect to viewer 24, the correct height is known forthat particular desired tool and tool holder assembly.

In another embodiment, the optical viewer 24 is adapted for continuouslydetermining the position of the tool 36 with respect to the tool holder34. In addition, the controller 15 may be connected to the viewer 24 andthe tool 36 and tool holder 34 such that the optical viewer 24continuously detects the actual position of the tool 36 with respect tothe tool holder 34 and sends an electronic signal to the controller 15indicating the actual position. In response, the controller 15 comparesthe actual position with the desired position and moves the tool 36 withrespect to the tool holder 34 until the desired position is achieved.

The heating device 14 includes a heater 28 mounted on a slide tower 30.The position and operation of the heater 28 is controlled by thecontroller 15. Although two controllers 15 have been disclosed, it willbe appreciated by those of ordinary skill in the art that a singlecontroller or any other type of control unit could be used to performthe operation and positioning of the heater 28 and optical viewer 24.

With reference to FIG. 2, the alignment device 16 will be described. Thealignment device 16 includes a spindle 32 for holding the tool holder34. In the preferred embodiment, the tool holder 34 is held within thespindle 32 through a vacuum clamp. The tool to be mounted within thetool holder 34 is shown generally at 36. A push rod 38 is adapted toreciprocate through the spindle 32 and tool holder 34 to engage theshank 40 of the tool 36. The engagement of the rod 38 with the shank 40may be such that they are removably attached, coupled so that the tool36 rests on top of the rod 38 or any other suitable means of coupling ormating such that the rod 38 may move the tool 36 within the tool holder34 to the desired position.

The rod 38 is removably mounted to an adjustable mount 42. In thedisclosed embodiment, the rod 38 is mounted to the mount 42 through anadjustable screw 44. The rod 38 is removably mounted so that differentrod sizes can be used or the rod 38 can be replaced if it becomes worn.However, it should be appreciated that wear of the rod is not importantto the proper operation of the present invention since the rod itself isonly used as a push rod for positioning the tool 36 with respect to thetool holder 34 and the viewer 24. This operation will be described ingreater detail below.

The mount 42 is connected to an adjustment device comprising an airslide 46 and an adjustment shaft 48. In the preferred embodiment, theair slide 46 provides for rapid adjustment and the shaft 48 provides forfine adjustment. The fine adjustment in the disclosed embodiment isachieved through a gear box 50 and an electronic control 52. System airis controlled through electronic controls 54 which control pressurizedair through air lines 56. The electronic controls 52, 54 are coupled tothe controller 15.

A housing top surface is shown at 58 and a mounting bracket is shown at60. The top surface 58 and the mounting bracket 60 form the support forsupporting the alignment device 16 with respect to the heating device 14and measuring device 12.

With reference to FIG. 3, the operation of unit 10 will be described. Inoperation, the push rod 38 is initially moved to its lowest position. Inthis position, the push rod 38 can be replaced if necessary. Asdiscussed above, replacement of the push rod may be required if therehas been damage to the push rod or undue wear or if a different sizepush rod is required for a specific mounting operation. The controlpanel 18 for controlling the push rod 38 is illustrated schematically.The down button 61 would be engaged to move the push rod 38 down.

After the push rod 38 is down, the tool holder 34 is then placed in thespindle 32. The vacuum clamp is energized by pushing button 63 on thecontrol panel 18. This holds the tool holder 34 within the spindle 32.It is contemplated that a standard vacuum clamp would be employed or anyother suitable means of retaining the tool holder 34 within the spindle32.

At this point in the operation, if there is an existing tool 36 mountedwithin the tool holder 34, i.e., the intent is to replace the tool 36,the push rod 38 would be raised to touch the bottom of the cutting tool36. This would be controlled by a push rod up button 65. Then eithermanual measurement of the tool 36 and tool holder 34 would be done orthe measuring device 12 would be set at the predetermined dimension forthe tool 36 and tool holder 34.

The heating unit 14 would then be programmed through the controller 15which in this embodiment is being shown with the same numeric indicationas the push rod controller 15 and vacuum control. Again, as indicatedabove, these various controllers could be a single unit or various unitsto control the various operations of unit 10. The controller 15 wouldinitiate heating of the heater 28 and also move the heater 28 intoposition so that the bore 64 in the heater is positioned over the boreof the tool holder 34 to heat that region and expand it for receipt ofthe shank 40 of tool 36.

As illustrated in FIG. 3, the heater slide 30 is mounted through bracket62 to the spindle 32 of the alignment device 16. Once the tool holder 34is properly heated, the heating device 28 will move away from the toolholder 34 and either the existing tool 36 can be removed and a new toolinserted into the bore. Or if it is a first time assembly, a new tool isinserted. A fine adjustment knob 67 is then used to raise or lower thetool 36 to the crosshairs of the optical viewer 24. Once the tool 36 isproperly within the crosshairs of optical viewer 24, the properalignment between tool 36 and tool holder 34 has been achieved. Thevacuum clamp is then released by pushing vacuum clamp button 63 and thetool holder 36 and tool 34 are removed from the spindle 32 and placedinto a cooling rack for complete cooling.

The foregoing detailed description shows the preferred embodiments ofthe present invention are well suited to fulfill the objects of theinvention. It is recognized that those skilled in the art may makevarious modifications or additions to the preferred embodiments chosenherein to illustrate the present invention, without departing from thespirit of the present invention. Accordingly, it is to be understoodthat the subject matter sought to be afforded protection should bedeemed to extend to the subject matter defined in the appended claims,including all equivalents thereof.

The invention has been described in an illustrative manner, and it is tobe understood that the terminology that has been used is intended to bein the nature of words of description rather than limitation. It will beapparent to those skilled in the art that many modifications andvariations of the present invention are possible in light of the aboveteachings. Therefore, it is to be understood that the invention may bepracticed otherwise than as specifically described within the scope ofthe amended claims.

What is claimed is:
 1. A tool assembly unit for coupling a tool and atool holder, said unit comprising: a measuring device for determining aposition of the tool with respect to the tool holder and establishing adesired position of the tool with respect to the tool holder; analignment device adjacent to said measuring device for receiving thetool holder and including a moveable rod for engaging the tool; and anadjustment device coupled to said moveable rod for moving said moveablerod to move the tool with respect to the tool holder to the desiredposition.
 2. A tool assembly unit as set forth in claim 1 wherein saidalignment device defines an aperture for slideably disposing saidmoveable rod therein.
 3. A tool assembly unit as set forth in claim 1wherein said measuring device includes an optical viewer disposedthereon for determining a position of the tool with respect to the toolholder.
 4. A tool assembly as set forth in claim 3 including acontroller coupled to said optical viewer and said alignment device forcontrolling said moveable rod in response to input by a user.
 5. A toolassembly as set forth in claim 3 including a controller coupled to saidoptical viewer and said alignment device for controlling said moveablerod in response to feedback from said optical viewer.
 6. A tool assemblyunit as set forth in claim 1 including a controller coupled to saidmeasuring device and said alignment device for controlling each of saiddevices.
 7. A tool assembly unit as set forth in claim 1 including awork table having said measuring device being mounted thereon.
 8. A toolassembly unit as set forth in claim 1 further including a mount havingan adjustable screw for removeably mounting said moveable rod therewith.9. A tool assembly unit as set forth in claim 1 wherein said adjustmentdevice comprises an air slide and an adjustment shaft.
 10. A toolassembly unit for coupling a tool and a tool holder by heat shrinking,said unit comprising: a measuring device for determining a position ofthe tool with respect to the tool holder and establishing a desiredposition of the tool with respect to the tool holder; an alignmentdevice adjacent to said measuring device for receiving the tool holderand including a moveable rod for engaging the tool; a heating deviceslideably mounted on said alignment device for heating the tool holderto facilitate coupling of the tool therewith; and an adjustment devicecoupled to said moveable rod for moving said moveable rod to move thetool with respect to the tool holder to the desired position after saidheating device has heated the tool holder.
 11. A tool assembly unit asset forth in claim 10 wherein said alignment device defines an aperturefor slideably disposing said moveable rod therein.
 12. A tool assemblyunit as set forth in claim 10 wherein said measuring device includes anoptical viewer disposed thereon for determining a position of the toolwith respect to the tool holder.
 13. A tool assembly as set forth inclaim 12 including a controller coupled to said optical viewer and saidalignment device for controlling said moveable rod in response tofeedback input by a user.
 14. A tool assembly as set forth in claim 12including a controller coupled to said optical viewer and said alignmentdevice for controlling said moveable rod in response to feedback fromsaid optical viewer.
 15. A tool assembly unit as set forth in claim 10including a controller coupled to said measuring device, said alignmentdevice, and said heating device for controlling each of said devices.16. A tool assembly unit as set forth in claim 10 including a work tablehaving said measuring device being mounted thereon.
 17. A tool assemblyunit for coupling a tool and a tool holder by heat shrinking, said unitcomprising: a measuring device including an optical viewer fordetermining a position of the tool with respect to the tool holder andestablishing a desired position of the tool with respect to the toolholder; an alignment device adjacent to said measuring device anddefining an aperture for receiving the tool holder; a heating deviceslideably mounted on said alignment device for heating the tool holderto facilitate coupling of the tool therewith; a moveable rod slideablydisposed within said aperture of said alignment device for engaging thetool; an adjustment device coupled to said moveable rod and including anair slide and an adjustment shaft for moving said moveable rod to movethe tool with respect to the tool holder to the desired position aftersaid heating device has heated the tool holder; and a controllerprogrammed for controlling said adjustment device to control a positionof said moveable rod to vary the position of the tool with respect tothe tool holder until the tool is in the desired position with respectto the tool holder.